The present invention relates to novel benzene derivatives which promote production or secretion of nerve growth factor (abbreviated to "NGF"), while exhibiting weak side effects.
The discovery of NGF was reported by Levi-Montaleini et al. in 1954. NGF is a nutrient and growth factor necessary for growth and for functional maintenance of nerve tissues. Recently from studies on animals, it has become known that NGF accelerates restoration of injured peripheral nerve tissue and that NGF is effective in the therapy of central nervous dysfunction, especially Alzheimer's disease and cerebral ischemia.
However, NGF is a high molecular weight protein (having a molecular weight of 13000 for the monomeric form, and 26000 for the dimeric form), and so there are problems associated with its administration as a drug and general concerns for safety.
It is also known that catechol neurotransmitters such as adrenaline and noradrenaline, and catechol analogs, can promote NGF formation. These compounds have side effects, particularly in nerve excitation.
European Patent Specification 399,814 published on 28 November 1990 discloses phenol derivatives which promote the production and secretion of human nerve growth factor. Related compounds of similar utility are disclosed in Japanese Patent Application 1-217211 which was filed on 25 August 1989 and published as Japanese Patent Kokai 3-83921 on 09 April 1991.